Modification of cellulosic textiles with combination of a divinyl sulfone monoester and an aminoplast resin or with a reaction product of said monoester and said resin



United States Patent MODIFICATION OF CELLULOSIC TEXTILES WITH COMBINATION OF A DIVINYL SULFONE MONO- ESTER AND AN AMINOPLAST RESIN OR WITH A REACTION PRODUCT OF SAID MONOESTER AND SAID RESIN William L. Mauldin and Donald J. Gale, Spartanburg,

S.C., assignors to Deering Milliken Research Corporation, Spartanburg, S.C., a corporation of Delaware No Drawing. Continuation of application Ser. No. 96,673, Mar. 20, 1961. This application Sept. 28, 1966, Ser. No.

21 Claims. (Cl. 8116.2)

ABSTRACT OF THE DISCLOSURE A process which comprises heating a dry, essentially unswollen cellulosic textile material to an elevated temperature, impregnating the textile material with an acid acting catalyst and the reaction product of a methylol textile resin and an ester of a sulfone or sulfoxide, the reaction product having at least one functional group which is reactive to cellulose under textile resin curing conditions and at least one activated ester group which is substantially inert under such curing conditions but which is reactive to the cellulose in the presence of a strong aqueous base. The reaction product is chemically fixed to the textile material and thereafter is impregnated with a strong aqueous base so that the textile material is crosslinked by the reaction product. At least one linkage occurs while the textile material is in a dry, essentially unswollen condition and at least one linkage occurs while the textile material is in a wet, essentially swollen condition.

This invention relates to methods for treating cellulosic textile materials to improve certain characteristics thereof, to the textile materials thus obtained and to novel compounds and compositions.

According to this invention, a cellulosic textile material as defined hereinafter, impregnated with a polyfunctional organic compound having both an acid reactive group and a base reactive group, is heated under textile resin curing conditions in the presence of a textile resin catalyst, to chemically fix the compound to the cellulosic material by the reaction of the acid reactive group while the textile material is in a dry, unswollen condition, and then contacting the resulting product with strong aqueous base to further chemically fix the compound to the cellulosic material by the reaction of the base reactive group while the textile material is in a wet, swollen condition, thereby producing a product having improved dry and wet resiliency. In its preferred embodiments, the step employing strong aqueous base can be eliminated while retaining many of the advantages of this invention.

It is now well known that cellulosic materials can be treated with a textile resin to impart certain minimum care characteristics to fabrics produced from these textile materials. As a result of this textile resin treatment, fabrics having fairly satisfactory dry resiliency, i.e., good dry crease resistance or recovery, are presently being commercially produced in large quantities. It is characteristic of such fabrics, however, that they must normally be drip dried, i.e., hung dripping wet after being washed, it the fabric is to have a semblance of a pressed appearance when dried. The reason for this is that although substantial dry resiliency is imparted to the fabric, a lesser degree of wet resiliency, i.e., wet crease resistance or recovery, is imparted to the fabric by the resin treatment. It is impractical to attempt to overcome this deficiency by applying more resin as severe embrittlement Patented Dec. 24, 1968 or weakening of the material results along with other undesirable features such as a harsh, raspy hand and poor comfort values if the material is to be used in a garment.

It has been found that this inherent deficiency of resin treatments can be overcome to a large degree by an additional treatment of the fabric with a wet cross-linking agent, i.e., a reagent which will cross link the cellulose while the fibers are in a wet, swollen condition. Fabrics can be produced by this combination of treatments having satisfactory dry and wet resiliency. Unfortunately, each of these steps results in a weakening of the material, although to a lesser degree than would be expected, in view of the weakening that is obtained from either step alone. Nevertheless, a loss of strength occurs sufficient to preclude the use of this combination of steps on some of the relatively weak starting cellulosic materials.

By the process of this invention, it is now possible to produce fabrics having satisfactory wet and dry resiliency while retaining a higher percentage of the strength of the starting textile material. By this process, fabrics can be produced having residual strength as great as that obtained by a comparable textile resin treatment alone and in addition having good dry resiliency and markedly superior wet resiliency. Fabrics can also be produced having at least as good dry and wet resiliency but greater residual strength. Frequently, fabrics having both increased residual strength and increased wet resiliency and about the same or greater dry resiliency can be obtained. Other properties are enhanced also, e.g., flex abrasion resistance is markedly increased, sometimes four fold, over fabrics treated by a typical resin treatment.

It is therefore an object of this invention to provide a novel process for the production of textile materials having good wet and dry resiliency.

It is another object to provide a novel process for the production of textile materials having a higher order of residual strength for any given degree of dry resiliency than can be obtained by a comparable resin treatment alone.

It is another object to provide a novel process for the production of textile materials having a higher order of residual strength for any given degree of wet resiliency than can be obtained by a comparable resin treatment alone.

It is a further object to provide a novel modified resin treatment of textile materials.

It is still another object to provide novel textile materials having a high degre of dry and wet resiliency and improved hand and other physical properties.

Another object is to provide novel chemically modified textile materials.

Still another object is to provide novel compounds and compositions.

Other objects will be apparent to those skilled in the art to which this invention pertains.

Textile materials which can be treated according to the process of this invention are those in which the anhydroglucose units are chemically substantially unmodified. Thus, the term cellulosic textile material when used herein means any textile material comprising fibers within the above definition, e.g., cotton, linen, jute, flax, regenerated cellulose fibers, including viscose rayon, in the form of staple, yarn and fabrics. This invention is directed primarily and preferably to cellulosic textile fabrics knitted and preferably woven. However, the advantages of this invention can be achieved by treating the cellulosic fibers, yarns, or threads employed to produce these fabrics. The thus treated material, when woven or knitted into fabric will produce a fabric having better wet and dry resiliency than identical fabric woven from identical untreated yarn or thread. Moreover, the properties of the staple yarn and thread are modified in a desirable fashion. For example, the staple is less prone to compression into hard masses during wet or dry processing. Satisfactory results can be achieved employing cellulosic materials containing both cellulosic and non-cellulosic fibers, especially if the non-cellulosic fibers have minimum care characteristics of their own. For example, the wet and dry resiliency of fabrics formed from a mixture of glycolterephthalate, polyacrylic, or nylon filaments or fibers with cotton or rayon can be improved by this process. Obviously, if the non-cellulosic fibers have low minimum care characteristics, the improved characteristics of the materials treated according to the process of this invention will be more readily apparent when the cellulosic content of the fabric is substantial, e.g., about 40% or more by weight. As stated above, the invention is primarily directed to fabrics, preferably consisting essentially of cellulosic materials, especially cotton. Bleached and usually also commercially mercerized or printed fabric, e.g., printcloth, broadcloth, and oxfordcloth, is usually employed as the starting fabric. Generally, it is preferred to employ starting fabrics having a tensile strength of at least 35 pounds and a tear strength of at least 400 grams in both the filling and Warp.

The polyfunctional organic compounds employed to impart wet and dry resiliency to the starting textile materials are those having both an acid reactive group and a base reactive group, i.e., compounds which will react with the cellulose under acidic conditions and will also react with the cellulose under basic conditions. As stated before, the purpose of this polyfunctionality is to permit a certain portion of the chemical linkages between the textile material and the polyfunctional organic compound to occur while the textile material is in a dry, unswollen condition and a portion .of the chemical linkages to occur while the textile material is in a wet, swollen condition. This polyfunctionality permits achieving the dry resiliency obtained from a comparable resin treatment yet, surprisingly, the concommitant loss of strength of the textile material is often markedly less. Furthermore, a higher degree of wet resiliency is often achieved than is ordinarily obtained with a usual resin treatment, even before the treatment of the resulting product with strong aqueous base. Moreover, when the treatment with strong aqueous base is undertaken, any loss of strength from this step is of a very low order and frequently there is no significant loss in strength. The net result is that fabrics having a level of performance equal to or greater than those of the prior art are obtained and having, e.g., from to 40% greater residual strength.

As stated above, some of the advantages of this invention become apparent immediately after the reaction of the polyfunctional compound with the cellulosic textile material under textile resin curing conditions. For example, greater residual strength is maintained in the fabric or an increase of at least one of dry and Wet resiliency is observed, compared with an identical treatment in which the polyfunctional compound is omitted. In ther Words, if substantially the same strength is obtained, a marked increase in flat drying properties is observed. If greater residual strength is obtained, then dry or Wet resiliency is found to be as good or substantially improved. It is for this reason that the process of this invention in its preferred embodiments is directed to the one step of reaction under textile resin curing conditions.

There are, however, reasons for employing the step of reacting the resulting product with strong aqueous base. One of these is that an even greater degree of dry and wet resiliency can be obtained after the second step without materially affecting the residual strength. The permanency of the treatment tends to be improved by the second step. Resistance to chlorine damage is often markedly improved by the second step. While this feature is not of material importance if the textile material is or is to be converted to colored goods or other goods which are not ordinarily bleached with hypochloride bleach, this factor is of considerable importance for white goods. Moreover, the step employing strong base tends to fix a higher percentage of the base reactive group containing compound to the cellulosic material, thus increasing the efiiciency of utilization of this compound It will be apparent to those skilled in the art from the foregoing discussion that the complete structure of the polyfunctional compounds employed herein is not critical so long as it contains at least one acid reactive group and at least one base reactive group as defined herein. Thus, compounds of relatively simple structure, such as N- methylol-N'-(sodium sulfatoethyl sulfonyl-ethyl) urea, which is the reaction product of monomethylol-urea and divinyl sulfone, can be employed. The acid reactive groups are generally those found in the textile resins presently employed in the resin treatment of cellulosic fabrics, e.g., methylol, epoxy, acetal, alkylated methylol, aldehyde, etc. These groups are characterized by their ability to combine with the hydroxy groups of the cellulose molecule under textile resin curing conditions. The base reactive groups are those which have the capacity of reacting with the hydroxy groups of the cellulose molecule in the presence of strong base and include epoxy and halohydrin groups and carbonyl, acetylenic, sulfone and sulfoxide activated groups, e.g., of the formula wherein R is a carbonyl, sulfone, sulfoxide or acetylenic group and R is sulfatoethyl, alkali-metal sulfatoethyl, phosphatoethyl, alkali-metal phosphatoethyl, thiosulfatoethyl, and alkali-metal thiosulfatoethyl, quaternary ammonium ethyl halides, e.g., yridinium ethyl chloride, vinyl or substituted, e.g., loWer-alkyl substituted, vinyl. Both the acid reactive and the base reactive groups can be epoxy if one of the epoxy groups has a lower order of activity than the other under textile resin curing conditions so that it does not, at that step, react with the cellulose. Employing a mild catalyst such as, for example, zinc chloride, magnesium chloride, or an amine hydrochloride will facilitate such a preferential reaction.

The amount of acid and base reactive group containing compound which can be employed is not critical and the exact amount to be employed depends, in part, on the properties desired in the final product and the efiiciency of the selected compound. For example, amounts in the range of from about 1% to 40%, preferably about 5% to 25%, calculated on the weight of the dry textile material, can be applied to the textile material. As the pickup of solution of the selected compound, if it is supplied as a solution, will range from about 50% to 200% of the weight of the textile material, a solution concentration should be selected which will provide the desired deposition of compound on the selected textile material under the conditions of pick-up.

Although, it is sometimes advantageous to apply to the textile material a single compound having both acid reactive and base reactive groups in the molecule, it is often more convenient to apply to the textile material a mixture of compounds which, under the textile resin curing conditions or conditions employed prior thereto, is converted to a compound having the requisite acid and base reactive groups. For example, a polymethylol textile resin can be mixed with a compound having both an aliphatic hydroxy group and a base reactive group in the molecule The hydroxy group of the latter compound will then react with a reactive group of the textile resin, ordinarily amethylol group, in a manner analogous to the known reaction of lower alkanols with the methylol aminoplast textile resins. This reaction can also occur in an aqueous solution of a mixture of these compounds, especially if the mixture is heated, in which case the resulting product Would fall within the definition of a compound having both acid reactive and base reactive groups in the molecule. On the other hand, the reaction between the two compounds can occur while the textile material, impregnated with the mixture of compounds, is heated, e.g., when drying the textile material, if the mixture of compounds is applied as an aqueous solution, or while the textile material is being heated under textile resin curing conditions.

The known polymethylol textile resins constitute a large class of compounds which can be employed to contribute the acid reactive group to the polyfunctional compounds employed in the processes of this invention. The term textile resin as used herein is in conformity with the generally accepted usage in the textile art, i.e., it defines a thermosetting reagent which is applied to a textile fabric and reacted therewith when the dry fabric is heated, usually in the presence of an acidic catalyst, at a temperature usually between about 140- to 200 C. At this temperature, the reagent, even by itself, will ordinarily resinify in the presence of an appropriate catalyst, thus probably contributing to the use of the term resin treatment. However, it is to be understood that the term as used in the textile art is a misnomer in that in contradistinction to the generally accepted meaning of the term resin, textile resins are of relatively low molecular weights, are almost always water soluble and are often liquids. Included in the class of textile resins are ureaformaldehyde and the melamine-formaldehydes, e.g., dimethylol-urea and tetraand penta-methylol-melamines, the acrolein-urea-formaldehyde resins, the cyclic ethylene urea-formaldehyde resins, e.g., dimethylol cyclic ethylene urea and dimethylol dihydroxy cyclic ethylene urea, trimethylol-acetylene diurea and tetra-methylolacetylene diurea, the triazones, e.g., dimethylol-N-ethyl-triazone, dimethylol-N-hydroxyethyl-triazone and N, N-ethylene-bisdimethyloltriazone, and the urons, e.g., dimethylol uron. Preferred are dimethylol-dihydroxy-cyclic ethylene urea and dimethylol-N-hydroxyethyltriazone.

These aminoplast textile resins exemplify the wide variety of structures which can be used to contribute an acid reactive group to the polyfunctional compounds employed in the process of this invention. Other non-nitrogen containing textile resins can also be employed, e.g., the epoxy and acetal textile resins. It will be obvious to one skilled in the art that the choice of compound employed to contribute the base reactive group will be influenced by the functional groups present in the compound contributing the acid reactive group.

Compounds which can be employed to contribute the reactive group to the polyfunctional compounds employed in the process of this invention include polyhydroxy compounds, at least one hydroxy group of which is activated and esterified. Esters of activated hydroxy groups can be carried through the heating step under textile resin curing conditions and will then be available to react with the cellulose molecule in the presence of strong aqueous base. The unesterified hydroxy group is available to react with the compound contributing the acid reactive group, e.g. an aminoplast textile resin, thereby producing a polyfunctioial compound having both acid and base reactive groups. A novel class of compounds within the above definition are the monoesters of di-B-hydroxyethyl-sulfone and of di-B-hydroxyethyl-sulfoxide. The mono-ester can be the sulfate, phosphate, or thiosulfate, preferably in the form of their alkali-metal salts, or an organic ester, e.g., lower alkanoate, or other alkyl, aryl, alkaryl, or arylalkyl ester, preferably hydrocarbon and containing from 1 to 12 carbon atoms. Because of the activated character of the hydroxy groups of the starting compounds, the mono-esters thereof can readily be prepared by employing a mole of the esterifying reagent per mole of the starting dihydroxy compound. Only very mild esterification conditions are required. For example, the sulfato mono-ester can be prepared at room temperature with about two molar equivalents of concentrated sulfuric acid. The reaction product can be converted to an alkali-metal salt by pouring into ice water and then carefully neutralizing to a pH of about 4 with, e.g., sodium carbonate. A method of producing an alkali-metal salt directly involves mixing the starting dihydroxy compound with about a molecular equivalent of sodium or potassium bisulfate and then heating while removing the water of reaction, usually with an azeotropic solvent. These monoesters can then be reacted with an aminoplast polymethylol textile resin either prior to applying the compounds to the selected textile material or subsequent thereto.

Examples of compounds containing acid and base reactive groups which can be used in the process of this invention are the reaction products of the sodium salt of the sulfato mono-ester of di-B-hydroxyethyl-sulfone with dimethylol urea, dimethylol-N-ethyl-triazone, dimethylol- N-hydroxyethyl-triazone, dimethylol cyclic ethylene urea, or dimethylol-dihydroxy-cyclic ethylene urea, and the reaction products of the corresponding acetic acid monoester with each of the above textile resins.

It has been established that a reaction between the above described mono-esters and textile resins does occur in situ on a selected textile material when an aqueous mixture of these compounds is applied to the textile material, the material dried and then cured in the presence of an acidic catalyst under textile curing conditions. This fact was established by the retention of the sulphur atom of the sulfone or sulfoxide group in the textile material when thereafter thoroughly washed, prior to being contacted with strong aqueous base. When the corresponding diester, i.e., disodum di-B-sulfatoethyl-sulfone, was substituted for the corresponding mono-ester, only insignificant amounts of sulphur were retained in the textile material when it was thoroughly washed immediately after the curing step.

Outstanding results are obtained when employing the reaction product of one of the above-described monoesters of di-/9-hydroxyethyl-sulfone and a polymethylol aminoplast textile resin to provide the acid and base reactive group containing poly'functional compound. These reaction products therefore constitute a preferred class of compounds to be employed in the process of this invention. A reaction temperature of between about and C. is preferred.

The molar ratio of polymethylol aminoplast textile resin and base reactive group containing compound, used to produce the acid and base reactive group containing polyfunctional compounds employed in the process of this invention, is not critical as satisfactory results have been obtained when the molar ratio was varied from as low as 1:2 to as high as 2: 1. This may be due to the fact that the reaction between the two compounds does not proceed to theoretical completion or the resultant compound rearranges to a certain extent to permit fixation of a portion of the resultant mixture to the cellulose during the heating step under textile resin curing conditions. In any event, the fixation occurs at least partially during the heating step and partially during the treatment with strong aqueous base.

The amount of selected compound containing the acid reactive group and the amount of selected compound containing the base reactive group which should be employed in the process of this invention will depend, of course, on the selected ratio between them which produces optimum results. Generally, from about 2% to about 25% of each compound is employed, calculated on the weight of the dry textile material. If a textile resin is employed to supply the acid reactive group, solution concentrations of between about 3% and 40% of each compound can be employed to apply them to the selected textile material.

The textile resin catalysts employed during the heating step under textile resin curing conditions are a wellknown class of compounds and include the acid acting compounds, i.e., those acidic in character under the curing conditions. The most common are the metal salts, e.g.,

magnesium chloride, zinc nitrate, and zinc fiuoroborate, and the amino salts, e.g., monoethanolamine hydrochloride and 2-amino-2-methyl-propanol nitrate. The amounts of catalyst to be employed are the same as those employed when using the usual textile resins, e.g., up to about 20% by weight of the polyfunctional compound employed, with the preferred range being from about 0.5% to about Other additives commonly employed when using the usual textile resins can be employed in the process of this invention. For example, a small amount of a surfactant can be added to insure uniform and satisfactory wetting out of the fabric, if an aqueous solution is employed. Softeners, e.g., the dispersible polyethylenes, can be added to improve tear strengths if the textile material being treated is fabric.

The strong aqueous bases employed in the second ste of process of this invention are those having a pH of at least 10 as a 1% aqueous solution. The bases most commonly employed are the alkali-metal hydroxides, although other compounds such as sodium silicate, sodium carbonate, and potassium carbonate can also be employed. These bases are usually employed as about 0.2% to about 16% solutions, preferably about 2% to about 16%. The exact concentration, while not critical, will affect the results obtained. The concentration which gives the optimum result will depend, in part, on the percent pick-up of the base by the textile material, the temperature at which the reaction is conducted, and the amount of base consumed in the reaction. If a highly acidic group is released during the reaction, e.g., when employing a sulfato ester containing compound, the amount of base applied to the textile material should be at least the amount that will be consumed by that group. Generally, a 3% to 10% aqueous solution of base is preferred when the pick-up is between about 30% to 130%, calculated on the weight of the dry textile material.

In carrying out the heating step of the process of this invention the cellulosic material, uniformly impregnated with a polyfunctional organic compound having at least one acid reactive group and at least one base reactive group is heated under textile resin curing conditions in the presence of an acidic catalyst. As stated before, this acid and base reactive compound can be that which is initially applied to the textile material or can be the product of an in situ reaction of an acid reactive group containing compound and a base reactive group containing compound. Under ordinary conditions, this step employs conditions identical to that of a conventional resin treatment. For example, the selected reagents can be applied to the textile material by padding, spraying, or applicator roll and then passed through squeeze rolls, if necessary, to achieve the desired pick-up of the reagents. As these reagents are ordinarily applied as aqueous solutions, the textile material is dried and then heated to the appropriate temperature, e.g., about 100 to 200 C., preferably about 140 to 190 C., to fix the compound to the textile material. When employing fabric these steps of drying and curing are conducted while the fabric is free from extraneous wrinkles, usually in a smooth, open width condition. Conventional curing equipment is suitable for this operation. For example, when employing a fabric, the reagents can be applied with the usual equipment and then passed through squeeze rolls and dried, e.g., at room temperature or while the fabric passes through a hot air oven or over heated cans. In production it is preferred to conduct the heating operations in a tender frame to maintain the desired dimensions.

The thus treated textile material is then ordinarily given a thorough wash to remove the catalyst and any nnreacted reagents. If suflicient reagents are employed in this step, the textile material will be found to possess a high degree of both dry and wet resiliency at this stage. However, for the reasons stated above, the textile material is ordinarily thereafter contacted with strong aqueous base.

The step of contacting the textile material with strong aqueous base employs conditions generally employed in the textile trade, and the necessary techniques will be apparent to those skilled in the art. For example, impregnating the textile material with the selected reagents can be accomplished in a manner similar to those employed in the previous step. The material can be moistened by dipping in an aqueous solution of the selected base, squeezed through rollers to achieve the desired pick-up of the base and then maintained at the selected temperature for a time suflicient to insure complete reaction. It is ordinarily not preferred to maintain the textile material in the presence of a large excess of the aqueous base solution because of the tendency of large excesses of base and water to sometimes interfere with the desired reaction. For this reason, the textile material is ordinarily maintained with a pick-up of from about 30% to 130%, calculated on the weight of the dry textile material. The preferred pick-up is from about 50% to 100%.

The temperature at which the reaction with the strong aqueous base is conducted can be varied over a fairly wide range, e.g., from about 20 to 100 C., preferably to C. Room temperature is preferred for its convenience. The thus treated textile material is ordinarily then given a thorough wash to insure removal of any excess base and any byproducts of the reaction.

The physical properties of the fabrics treated according to the process of this invention were determined according to accepted standard methods. Tear strength was determined by A.S.T.M. Test designation D-1424-59. Tensile strength was determined by A.S.T.M. Test designation D-39-59 (No. 10). Crease recovery angle was determined by A.S.T.M. Test designation D1295-53T. See A.S.T.M. Standards for Committee D-13 on Textiles (1959). Flat dry ratings were by A.A.T.C.C. Test designation T-88-l958.

The following is illustrative of the processes and aqueous emulsion containing 30% polyethylene solids, Surfonic N- refers to an ethylene oxde condensation product of nine parts ethylene oxide and one part nonyl phenol, and Mercerol GV refers to an anionic ether derivative free of cresylic acid.

The following is illustrative of the processes and products of this invention, but is not to be construed as limiting.

In the following examples, Moropol 700 refers to a nitrogen-free nonionic polyethylene emulsion used in conjunction with thermosetting resins (Technical Manual of AATCC, vol. 36, page 527, copyright 1960, AATCC, Lowell, Mass); Aerotex Resin 23 refers to a triazineformaldehyde condensate (Technical Manual of AATCC; vol. 36, page 452); Rhonite N-17 refers to a liquid monomeric thermosetting resin (Technical Manual of AATCC, vol. 36, page 555); Surfonic N-95 refers to a nonionic alkyl aryl polyethylene glycol ether (Detergents and Emu1sifiers-up to date-1960, page 104, copyright 1960, John W. McCutchen, Inc.); Mercerol GV refers to a mixture of anionic surfactants free of cresylic acid, sold by Sandoz, see 1960 product bulletins.

EXAMPLE 1 1.0 mole (154 g.) of di-B-hydroxyethyl-sulfone was mixed with 1.0 mole g.) of sodium bisulfate at least partially dissolved in about 50 ml. of water. The mixture was heated with about 220 ml. of toluene in a 3-necked flask fitted with a stirrer and condenser having a Stark- Dean trap. The added water and water of reaction was removed azetropically with the refluxing toluene. When the added water and the theoretical amount of water of reaction had been removed, the mass was poured into cold water. The toluene was separated and the pH of the aqueous solution was adjusted to 4 with about 6.5 g. of sodium carbonate, indicating an 87% yield of sodium a-hydroxyethyl-B'-sulfatoethyl-sulfone. This compound can be isolated, if desired, by removing the water under vacuum. The compound was obtained as a highly viscous oil which defied crystallization. Hydrolysis with excess sodium hydroxide followed by titration with acid to determine the consumed base confirms the structure as does infrared and elemental analysis.

Similar results are obtained employing benzene or xylene as the azeotropic liquid.

EXAMPLE 2 1.0 mole (154 g.) of di-fi-hydroxyethyl-sulfone was melted in a reaction flask. To the melt was slowly added 1.0 mole (102 g.) of acetic anhydride. The acetic acid formed was removed under vacuum. There was thus obtained di-B-hydroxyethyl-sulfone monoacetate as a viscous oil. Hydrolysis studies indicated that the purity was at least 85%.

Following the above procedure, other esters of difihydroxyethyl-sulfone are prepared by reaction with the selected anhydride, to produce the propionate, butyrate, succinate, octanoate, chloroacetate, phenylacetate, phenylpropionate, benzoate, chlorobenzoate, or other alkyl, aryl, alkaryl or arylalkyl ester, particularly those containing up to twelve carbon atoms. The formate mono-ester is readily prepared from concentrated formic acid. The monoacetate can also be prepared from glacial acetic acid, preferably in the presence of an esterification catalyst, e.g., ptoluenesulfonic acid, and preferably also with removal of the water of reaction by 'azeotropic distillation.

EXAMPLE 3 Following the procedure of Example 1, sodium bisulfate was reacted with a molar equivalent of di-B-hydroxyethyl-sulfoxide, removing the water of reaction with benzene, to product sodium ,B-hydroxyethyl-p"-sulfatoethylsulfoxide.

This compound can be isolated by dissolving in water to make up a concentrated solution and then chilling the resulting solution.

EXAMPLE 4 770 g. (5.0 moles of di-B-hydroxyethyl-sulfone was melted (45 C.) in a 3-necked round bottom flask. 550 mls. (10.0 moles) of 96.6% H 50 was then added slowly, with cooling, so that temperature did not rise above 50 C. The reaction mass was then held at room temperature overnight.

Analysis of the sulfation mass, by carefully neutralizzinc nitrate, 0.5% surfactant (N-95), 6% of a polyethylene softener (Syn-soft E) and 17% sodium B-hydroxyethyl-B'-sulfatoethyl-sulfone. The solution padded onto 80 x 80, 4.0 yds./lb. (in the greige) bleached and mercerized 42 lb. filling tensile, printcloth with a pick-up of 80%. The fabric was dried on hot cans and then cured at 177 C. for 1.5 minutes, placed taut on a 9" x 12" pin frame and then immersed in 2% aqueous sodium hydroxide at 60 C. for one minute. The fabric was washed thoroughly and tested. It had a 4.0 spin and tumble flat dry ratings, a 445 g. dry filling tear and 27.7 lbs. dry filling tensile.

EXAMPLE 5 1.0 mole (256 g.) of dimethylol-N-hydroxyethyltriazone textile resin as a aqueous solution was mixed with 1.0 mole (256 g.) of sodium B-hydroxyethyl-;3'- sulfatoethyl sulfone as a 40% aqueous solution. The mixture was refluxed for about 2 hours. There was thus produced an aqueous solution of the reaction product of the resin and the sulfone. The thus produced reaction product can also be conducted at between about 80 and 190 C.

Similarly, resin mixtures were prepared in which the ratio of textile resin to sulfone were 2:1 and 1:2.

The dimethylol-N-hydroxyethyltriazone textile resin and sulfone aqueous reaction products prepared according to the procedure of Example 1 were made up to an aqueous solution of the following composition: about 22% textile resin-sulfone reaction product (solid), 1% zinc nitrate, 6% polyethylene softener (Moropol 700), and 0.5% surfactant (Surfonic N-95).

The resin mixture was applied to 80 x 80, 4.0 yds./lb. (in the greige) bleached and mercerized cotton printcloth by padding and then squeezing through nip rolls at lbs./ square inch pressure to provide a pick-up of about based on the weight of the dry fabric. The fabric was dried over hot cans and then cured by passing through a curing oven at about 175 C. for 1.5 minutes.

The cured favric was passed into a 3% aqueous sodium hydroxide solution containing 0.5 of a non-ionic surfactant (Mercerol GV) and then through squeeze rolls to provide a pick-up of about 60%, based on the weight of the dry fabric. The fabric was rolled up into a smooth roll and maintained at room temperature for about 15 minutes. The fabric was then rinsed in 1% acetic acid, rinsed with water and dried. The properties of the thus treated fabric are shown in Table I below.

ing the free acid of an aliquot portion to pH 4 with sodium carbonate, hydrolyzing the sulfato group with measured excess sodium hydroxide and then titrating the remaining base to determine the amount consumed, showedthat 50.6% of the hydroxyls had been sulfated. The mass was poured slowly into 3,540 g. of ice water, keeping the temperature below 20 C. Solid Na CO (770 g.) was then added, with cooling, to adjust the pH to 4.0, keeping the temperature below 20 C. The aqueous mixture was filtered, placed in an ice box at (5 C.) overnight and filtered again to remove the sodium sulfate. The filtrate was found, by analysis, to consist of 25% by weight of sodium ,s-hydroxyethyl-,8'-sulfatoethylsulfone.

This solution was made up into a solution containing 15% (7.5% solids) modified melamine resin (A-23), 1%

Following the above procedure, various textile resins can be combined with the sodium B-hydroxyethyl-H- sulfatoethyl sulfone, e.g., dimethylol-N-ethyltriazone, dimethylol-N-hydroxyethyltriazone and the corresponding dimethyl ether, dimethylol-cyclic ethylene urea, dimethylol-4,S-dihydroxy-cyclic ethylene urea, pentamethylol melamine, and urea-formaldehyde textile resins to provide novel cellulosic cross-linking agents and cross linked fabric.

EXAMPLE 6 The procedure of Example 4 was followed employing resin-sulfone mixtures and the bases shown in Table H below. The heating step was omitted, thereby permitting the reaction between the resin and sulfone to occur primarily on the dry cans as the fabric was dried. The prop erties of the thus treated fabrics are shown in Table II.

TABLE II Resin Dry Fill Filling Spin Tumble Sample Mixture Base Tensile Tear Flat Dry Flat Dry (1bs.) (g.) Rating Rating Control 46. 6 464 1.0 1.0 1 A 2% NaoH 27.2 430 4.1 4.0 2 A..." 4% NaO 29.5 460 4.2 4.2 3 A".-. 5% a 27.6 444 4.0 4.0 A 0 7 0 27.2 444 4.0 3.8 28.0 448 4.2 3.9 26.5 420 4.0 4.0 28.9 448 4.0 4.0 2% NaOH 27.1 384 4.0 4.0 0. 0-- 4% NaOH 25.0 372 4.0 4.0 5% Na0H 24.3 368 4.5 4.1 11..-

6% NaOH 24.0 368 4.0 4.6 12... 3% Nl2CO3 25.5 452 3.9 4.2 13 D 2% NaOH 29.3 424 3.9 4.0

Resin A Mixture: Percent EXAMPLE 8 Modlfied melamme resm (Aerotex 23 (sohds)' 5 Samples of bleached and mercerized 80 x 80, 4.00 yd./

Triazone resin (Rhonite N-17) (solids) 2.5 Sodium fl-hydroxyethyl-fi-sulfatoethyl-sulfone 10 Polyethylene softener (Moropol 700) 6 Catalyst (zinc nitrate) 1 Surfactant (Surfonic N-95) 0.5 Resin B Mixture:

Dimethylol cyclic ethylene urea Resin (Permafresh LF) (solids) 6 Triazone resin (Rhonite N-17) (solids) 2.5 Sodium S-hydroxyethyl-fi'-sulfatoethyl-sulfone 10 Polyethylene softener (Moropol 700) 6 Catalyst (zinc nitrate) 1 Surfactant (Surfonic N-95) 0.5 Resin C Mixture:

Triazone resin (Rhonite R-l) (solids) 5 Modified melamine resin (Aerotex 23) (solids) 2 Sodium B-hydroxyethyl-fi-sulfatoethyl-sulfone 10 Polyethylene softener (Moropol 700) 6 Catalyst (zinc nitrate) l Surfactant (Surfonic N-95) 0.5 Resin D Mixture:

Triazone resin (Rhonite N-17) (solids) 7.5

Sodium ,B-hydroxyethyl-fi'-sulfatoethyl-sulfone Polyethylene softener (Moropol 700) 6 Catalyst (zinc nitrate) 1.5 Surfactant (Surfonic N-95) 0.5

Following the above procedures, similar results are obtained by substituting an equal amount of sodium B-hydroxyethyl-/3-sulfatoethyl-sulfoxide for the sulfone in each of the resin mixtures described in Example 2.

EXAMPLE 7 The procedure of Example 4 was followed employing a resin mixture consisting of 4.5% (solids) of a modified melamine textile resin (Aerotex 23), 2.5% of a triazone textile resin (Rhonite N-17), 10% monoacetate of di-fihydroxyethyl-sulfone, 1% Zinc nitrate catalyst, 6% polyethylene softener (Moropol 700) and 0.5% surfactant (Surfonic N-95 Pick-up of the solution was substantially the same as in Example 4. The fabric was dried and cured for 1.5 minutes in a curing oven at 177 C. Samples identified as A were then tested for physical properties. Portions of the thus cured fabric, identified as B, were passed into 10% aqueous sodium hydroxide containing 1% surfactant (Mercerol GV) and maintained at room temperature for 15 minutes, washed with dilute acetic acid and then with water and detergent.

The thus treated fabrics had the following properties:

lb. (in the greige) printcloth padded with an aqueous solution containing 4.5 (based on solids) of a modified melamine resin. (Aerotex A-23), or 4% of a dimethylol cyclic ethylene urea resin (Permafresh LP) or 11% of a triazone resin (Rhonite N17), 0% or 10% of sodium ,B-hydroxyethyl-fl-sulfatoethyl-sulfone, 2% of a zinc nitrate type resin catalyst (Catalyst 100), 6% of a polyethylene softener (Moropol 700), and 0.33% of a surfactant (Surfonic N-95). The fabric was passed through nip rolls set at p.s.i. to provide a pick-up of the solution of about of the weight of the dry fabric, dried on dry cans and then cured while smooth at 176 C. for 1.5 minutes in a curing oven. A portion of each of these samples was tested for physical properties and the remaining portion passed into 4% aqueous sodium hydroxide containing 0.5% of a surfactant (Mercerol GV) and then I through nip rolls to provide a pick-up of about 60%,

calculated on the weight of the dry fabric. The fabric was maintained at room temperature for 15 minutes, washed in 0.5% acetic acid and then washed thoroughly with detergent and water. The resulting fabric was then tested for physical properties. The results of these tests are shown in Table IV below.

TABLE IV.X 80 PRINTCLOTH 10% HO CH2CH2SO2 0% No After NaO SOCH- ,CH: Base Before Base Base (4% NaOH) 0% resin:

44. 9 37. 8 756 544 1. 0 1. 0 Tumble 1. 0 1. 0 4.5% (solids) modified melamine resin:

Tensile 31. 3 30. 2 29. 7 434 448 412 3. 0 4. 0 3. 7 Tumble 3. 6 3. 7 4. 9 4% (solids) cyclic ethylene urea resin:

Tensile 26. 2 29. 0 26. 1 416 364 3. 7 3. 5 3. 6 4. 0

The sample containing 10% sodium fl-hydroxyethyl-B'- sulfatoethyl-sulfone but no textile resin did not have flat drying properties. The samples containing only the regular textile resin had low levels of performance whereas the samples containing the same amount of textile resin plus 10% of the sulfone compound had markedly improved performance both before and after the treatment with base, while retaining about the same or greater residual strength. These results show that the sulfone compound, by itself, contributes nothing to flat dry performance but when reacted with a textile resin works synergistically therewith to produce better results than is obtained by the same resin'alone.

13 EXAMPLE 9 Samples of the same starting fabric as that described in Example 8 was padded in the manner described therein with one of the following aqueous solutions:

Percent Modified melamine resin blend (Aerotex A-44) (solids) 7.5 Sodium B-hydroxyethyl-p?'-sulfatoethyl-sulfone or Magnesium chloride type resin catalyst (Catalyst MX) 3 or 4.5 Polyethylene softener (Moropol 700) 6 Surfactant (Surfonic N-95) 0.33

Portions of each of these samples were tested for physical properties. Other portions were treated with 4% or 6% aqueous sodium hydroxide. All other conditions were the same as those described in Example 8. The physical properties of each of the thus treated samples are shown in Table V below.

TAB LE V.-8OX 80 PRINTCLOIH HO-CHz-CHz-SO After After N aO;S-O OH2CH2 No Before Base Base Base Base (4% (6% NaOH) NaOH) 7.5% resin, 3% catalyst:

Tensile 17. 0 19. 7 19. 9 21. 6 316 312 312 312 3. 3 4. 2 5. 0 4. 3 4. 2 4. 0 4. 7 4. 9

In the samples containing the sodium ,8-hydroxyethyl-B- sulfatoethyl-sulfone the flat dry performance, particularly spin, was considerably improved both before and after the base treatment and the residual strength was greater in most instances.

EXAMPLE 10 Samples of the same starting fabric as that described in Example 8 was padded in the manner described therein with one of the following aqueous solutions:

Percent Cyclic ethylene urea resin (Permafresh LF) (solids) 6 Monoacetate of di-fi-hydroxyethyl-sulfone 0 or 10 Zinc nitrate type resin catalyst (Catalyst X-4) 2 or 3 Polyethylene softener (Moropol 700) 6 Surfactant (Surfonic N-95) 0.33

All samples were then dried and cured for 1 or 1.5 minutes at 176 C. The samples impregnated with a solution containing the resin and di-p-hydroxyethyl-sulfone monoacetate mixture were then passed into 10% aqueous sodium hydroxide. All other conditions were the same as those described in Example 8. The physical properties of the thus treated fabric are shown in Table VI.

TABLE VL-BOX 80 PRINTOLOTH In each instance markedly superior spin flat dry performance was achieved in the samples padded with a solution containing both the textile resin and the di-flhydroxyethyl-sulfone monoacetate while retaining about the same or greater strength as the samples treated with textile resin alone.

EXAMPLE 11 Samples of bleached and mercerized 80 x 80 4.00 yds./ lb. (in the greige) printcloth and 136 x 64 3.19 yds./lb. broadcloth were uniformly impregnated, with a pick up of about to of an aqueous solution having one of the following compositions:

Percent Cyclic ethylene urea resin (Permafresh LF) (solids) 6 or 7.5 Sodium fl-hydroxyethyl-B'-sulfatoethyl-sulfone Zinc nitrate type catalyst (Catalyst X-4) 1.8 Polyethylene softener (Moropol 700) 6 Surfactant (Surfonic N-) 0.25

The samples were dried and then cured at 157 or C. for about 1 minute in a commercial tenter frame drying oven. Portions of these samples were padded through 4% aqueous sodium hydroxide to give a pick-up of about 60% and then stored for 15 minutes at room temperature. All samples were washed thoroughly with water and detergent. The physical properties of the thus treated fabric are shown in Tables VII and VIII.

TABLE VII.SO x 80 PRINTCLOTH HO--OH2-CH2SO2 0% 8% 10% 12% 15% NaO;SO-C H2CH2 Before After Before After Before After Before After Before After Base Base Base Base Base Base Base Base Base Base 6% resin, 157 C. cure- Tens 22. 4 21. 7 24. 9 22. 9 24. 3 Tear 324 320 388 344 356 Spin 3.3 3.4 3.3 3.9 4.4 Tumble 4. 0 4. 0 4. 0 4. 0 4. 0 6% resin, 165 C. cure:

Tensile 19. 8 21. 7 20. 5 21. 5 23.

20. 9 21. 5 22. 4 22. 4 24. 2 24. 2 300 304 340 324 368 360 3.3 3.1 3.9 4.4 4.0 4.6 4.6 4.0 4.7 4.9 4.3 4.4 7.5% resin, 165 C. cure:

TenS' e- 19. 1 19. 4 21.6 21. 1 22.1 21. 8 Tear- 276 260 308 304 332 312 Spin. 3. 3 4. 0 3.3 4.3 4.3 5.0 Tumble 5. 0 4. 4 4. 8 5. 0 4. 8 4. 9

TABLE Vl'lI.-l36 x 64 BROADCLOTH HO-CHzOHz-{S Oz 8% 12% N803S-O-CH2CH2 Before After Before After Before After Before After Base Base Base Base Base Base Base Base 6% resin, 157 C. cure:

Tensile 39. 7 38. 4 39. 1 36. 8 Tear..-- 704 720 756 668 Spin- 2. 9 2. 8 3. 2 4.0 Tumb 4. 1 4. 0 4. 0 4. 0 6% resin, 165

Tensile- 35. 1 33. 9 35. 7 36. 0 Tear 652 620 728 632 Spin 3. 3 3. 4 3. 7 4. 7 Tumble 4.6 4.0 4.2 4.6 7.5% resin, 157 0 ur Tensile"--- 35.0 37. l Tear- 596 692 Spin 3.0 3.0 Tumble 4. 8 4. 2

The improved spin flat dry performance in the fabrics treated with strong aqueous base before being washed was often accompanied by increased retained sulfur compared with the fabric cured and then washed, although it would be expected that the loss of half the sulfur atoms by removal of the sulfato group would reduce rather than increase retined sulfur. Retained sulfur is less if the fabrics impregnated with the resin and sodium fi-hydroxyethyl-18'- sulfa-toethyl-sulfone are cured and then washed before being treated with strong aqueous base and then rewashed. Under such conditions, up to half the sulfur present after curing and washing is removed with the strong base followed by washing. This agrees with the theoretical considerations. However, if the washing step after curing is eliminated, considerably greater amounts of sulfur are often retained, indicating that the strong aqueous base fixes sulfur containing material to the cellulose that is not fixed to the cellulose during the curing step. It thus appears that textile material cured and treated with strong aqueous base without an intermediate wash has some straight resin cross-linkages and some sulfone mono-linkages, as well as the expected cross linkages produced by the sulfone-resin reaction product. It is believed that this hetero nature of the linkages thus produced is at least partially responsible for the outstanding results obtained when using this combination of reagents.

While this invention has been described as directed to textile materials, it will be apparent that its usefulness extends to related fields such as the paper industry for producing wet and dry strength paper and paper products in a manner analogous to that described herein.

That which is claimed is:

1. The process which comprises the steps of (1) heating under textile resin curing conditions a dry, essentially unswollen cellulosic fabric whose anhydroglucose units are substantially unmodified and which is uniformly impregnated with an acid catalyst and a chemically reactive system selected from the group consisting of (a) a water soluble polymethylol aminoplast textile resin and a water soluble polyfunctional organic monoester represented by the formula HOCH CH S (o) CH -CH -OR wherein x is an integer from 1 to 2 and R is the residue of an organic carboxylic acid or an inorganic acid in alkali metal salt form and (b) the reaction product produced by refluxing said textile resin and said polyfunctional monoester at a temperature of from 80 C. to 190 C. at mole ratios of from 1:2 and 2:1, thereby causing reaction be tween said textile material and the reactive groups in said system which are responsive to acid catalysis; and (2) thereafter uniformly impregnating the modified textile fabric with a strong base while maintaining said textile fabric in a wet, swollen condition to catalyze further reaction between said fabric and the reactive system with which it is impregnated.

2. The process of claim 1 wherein the fabric is cotton and the textile resin is selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethylene ureas.

3. The process of claim 1 wherein the ester group is a sulfato ester.

4. The process of claim 1 where the chemically reactive system is the system designated, (a).

5. The process of claim 4, wherein the organic monoester is sodium B-hydroxyethyl-[i-sulfatoethyl sulfone.

6. The process of claim 4 wherein the textile resin is selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethylene ureas.

7. The process of claim 4 wherein the curing step is conducted at temperatures of from about C. to 200 C. and the fabric is contacted with the strong base at temperatures of from about 20 C. and 100 C.

8. The process of claim 4 wherein the weight ratio of polymethylol aminoplast textile resin to polyfunctional organic monoester is from 1:2 to 2: l.

9. The process of claim 4 wherein the polymethylol aminoplast textile resin is selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethyleen ureas and the strong base is an aqueous alkali-metal hydroxide of a concentration between about 2% and 16%.

10. The process of claim 9 wherein the textile resin is dimethylol N-hydroxyethyl-triazone.

11. The process of claim 9 wherein the textile resin is dimethylol-dihydroxy-cyclic ethylene urea.

12. The process of claim 1 where the chemically reactive system is the system designated, (b).

13. The process of claim 12 wherein the organic monoester is sodium ,B-hydroxyethyl-B-sulfatoethyl sulfone.

14. The process of claim 12 wherein the textile resin is selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethylene ureas.

15. The process of claim 12 wherein the curing step is conducted at temperatures of from about 100 C. to 200 C. and the fabric is contacted with the strong base at temperatures of from about 20 C. and 100 C.

16. The process of claim 12 wherein the polymethylol aminoplast textile resin is selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethylene ureas and the strong base is an aqueous alkali-metal hydroxide of a concentration between about .2 and 16%.

17. The process of claim 15 wherein the textile resin is dimethylol N-hydroxyethyl-triazone.

18. The process of claim 16 wherein the textile resin is dimethylol-dihydroxycyclic ethylene urea.

19. The process which comprises the steps of heating a cotton fabric at a temperature between about C. and C. for between about 1 and 3 minutes while the fabric is in a smooth condition and uniformly impregnated with between about 3% and 10% of textile resins solids selected from the group consisting of dimethylol urea, dimethylol triazones, polymethylol melamines and dimethylol cyclic ethylene ureas, between about 5 and 20% of sodium-B-hydroxyethyl-B-sulfatoethyl-sulfone, I all calculated on the dry weight of the fabric, and an acid actcatalyst for the textile resin, and thereafter impregnating the thus treated fabric with a strong base while maintain- 17 18 ing said fabric in a wet, swollen condition to catalyze No references cited. further reaction between said fabric and the reactants with which it is impregnate NORMAN G. TORCHIN, Primary Examiner.

20. A cellulosic fabric produced by the process of claim 0 ANN ON, Assistant Examiner, 4. 5

21. A cellulosic fabric produced by the process of claim 12. 

